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  • Simulating SDEs: the Euler–Maruyama scheme

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Euler–Maruyama against the exact solution

Both paths use the same Brownian increments. Fewer steps means a cruder Euler path; the error plot shows how fast it vanishes as the step shrinks.

Parameters

8
28
0.08
-0.30.3
0.40
0.10.8
Random seed: 7
Metrics
Error at T (this path)
4.36
Strong order (slope)
0.48
Weak order (slope)
1.00
One path, exact and Euler with n = 8 steps
Exact solutionEuler–Maruyama
Error against step size (log-log)
Strong error E|S_T − S̃_T|Weak error |E S_T − E S̃_T|Slope ½Slope 1Current n